New York Yankees starting pitcher Michael Pineda (35) is ejected from the game for having a foreign substance on his neck during the second inning against the Boston Red Sox at Fenway Park, April 23, 2014.

Bob DeChiara, USA Today Sports

That something turned out to pine tar. It was not there in the first inning, but it was clear as mud in the second. Opposing teams usually look the other way.

Not this time.

"I fully understand that on a cold night you want to get a good grip. But when it's this obvious, something has to be said," said Red Sox manager John Farrell.

Pitchers often ignore baseball's written rules and use pine tar to help control the ball. Dan Plesac pitched in the majors for 18 seasons.

"Not one game did I go out there without having some pine tar on my glove, on my sleeve, on my head," he said.

Plesac, now an analyst for the MLB network, says Pineda broke baseball's unwritten code by being so obvious.

"There is an unwritten code. Unfortunately, Michael Pineda didn't get the memo," he said.

"It almost looked like a Hershey bar on the right side of his neck," said Plesac. "It almost forced the Red Sox and everybody on the Red Sox bench to say, 'Look what he's doing!'"

In a game two weeks ago, Pineda had something on his hand. The Red Sox ignored it -- until Wednesday night, when he rubbed pine tar on his neck and in the game's face.

"I kind of equate this to getting pulled over by a police officer for speeding," said Plesac. "He pulls you over, he writes you a warning ticket. You get in the car and you do a burnout, a takeoff. You force the officer to pull you over and give you another ticket."

After the game, Pineda admitted to reporters that he broke the rules and apologized to his teammates. He said he'd never do it again. And on Thursday, he said he accepted his punishment.